3 papers
math.NA2025
Multicentric representation of piecewise constant holomorphic functions and Hermite interpolation
Olavi Nevanlinna, Tiina Vesanen
In multicentric representation of piecewise holomorphic functions one combines Lagrange interpolation at roots of a polynomial with convergent power series of as the "coeff…
math.FA2025
Metric functionals and weak convergence
Armando W. Gutiérrez, Olavi Nevanlinna
We introduce a notion of weak convergence in arbitrary metric spaces. Metric functionals are key in our analysis: weak convergence of sequences in a given metric space is tested ag…
math.FA2024
Subinvariant metric functionals for nonexpansive mappings
Armando W. Gutiérrez, Olavi Nevanlinna
We investigate the existence of subinvariant metric functionals for commuting families of nonexpansive mappings in noncompact subsets of Banach spaces. Our findings underscore the…